1. Field of the Invention
The present invention relates to 6,7-disubstituted-5,8-quinolindion derivatives as an antifungal agent expressed in the following formula 1 which has excellent antifungal activity against funges infecting human and animals, 
wherein
R1 represents phenylamino group substituted 1 to 3 with a substituent selected from the group consisting of a halogen atone and an aceto group, or C1-C20 alkylmercapto group; and
R2 represents thiocyano group; or C1-C20 alkylmercapto group.
2. Description of the Prior Art
The recent increase of fungal infections has generated a renewed interest in antifungal drugs, including development of new antifungal agents. We focused on developing 6,7-disubstituted-5,8-quinolinediones with noble mode of antifungal activities. As antimetabolites of coenzyme Q, the 6-(substituted)-7-chloro-5,8-quinolinediones inhibit mitochondrial Co-Q dependent succinoxidase and electron transport in Saccaromyces cerevisiae, that may be correlated with antifungal activity (Arch. Biochem. Biophys., 191, 306-315, 1978). The 5,8-quinolindiones, as antimetabolites of coenzyme Q, inhibit cytochrome bc complex due to blockade of mitochondrial electron transport in fungi (J. Med. Chem., 16, 206-209, 1973). 6/7-Substituted-5,8-quinolinedione derivatives have also been reported fungicide in German Patent Publication No. 4, 208, 874 (1993), but no antifungal activity against human pathogenic fungi was not tested or mentioned.
The present invention has been completed by synthesizing 6,7-disubstituted-5,8-quinolinedion derivatives and confirming the antifungal activity thereof.
Therefore, an object of the present invention is to provide 6,7-disubstituted-5,8-quinolinedion derivatives expressed in the formula 1, including its preparing method and use as an antifungal agent.